JPH06102179B2 - Method for producing multilayer coating film support - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a multi-layer coating film support which can be easily subjected to secondary processing without causing cracking or deterioration of adhesion.

[0002]

BACKGROUND OF THE INVENTION Physical properties of paints are of the utmost importance in the production of undercoat metals in multilayer coating substrates for the secondary processing of structural building components such as siding. Not only must the coating exhibit excellent durability properties and adherence to the support, it must also be sufficiently flexible to be fabricated without cracking or loss of adhesion. Therefore, it is necessary for the paint to show not only excellent flexibility but also good adhesion, cracking resistance and corrosion resistance at the edges of the secondary processed product.

[0003]

DISCLOSURE OF THE INVENTION The present invention uses the above-mentioned paint as a primer to prepare a multi-layer coating film support which can be easily subjected to secondary processing without causing cracking or deterioration of adhesiveness. The purpose is to provide the law.

[0004]

Means for Solving the Problems That is, the present invention comprises: (a) applying a flexible undercoat paint to a support, wherein the paint comprises (i) an isocyanate-terminated urethane-containing substance; (ii) Consisting essentially of phosphinated polyepoxides free of oxirane groups; (b) applying at least one pigmented coating to the coated support of (a); (c) the coated support obtained in step (b). To at least partially cure: a method of making a support having a multilayer coating comprising: the multilayer coating having an elongation of at least 50% when cured.

The paint used in the present invention consists of two major components. The first of these components is an isocyanate-terminated urethane-containing material. Preferably,
The material is a polyurethane prepared from a polyol component and an organic polyisocyanate.

In addition to the preparation from the polyol component and the organic polyisocyanate, the isocyanate-terminated urethane-containing material may be prepared by reacting the polyisocyanate with the reaction product of urea and the polyol. The urethane-containing material also contains the same proportion of urea groups.

Further, the urethane-containing substance having isocyanate as an end group is a reaction product of 1) an amino-containing substance such as an amine and a carbonate;
2) A reaction product of a carbonate with a mixture of an amino-containing substance such as an amine and a hydroxy-containing substance such as an alcohol;
Alternatively, 3) it may be prepared by reacting a reaction product of a hydroxy-containing substance such as alcohol with a carbonate.

In a preferred embodiment, the polyol component may be a single organic polyol or a mixture of organic polyols. Examples of suitable polyols include many ones such as acrylic polyols, polyester polyols, polyether polyols, polysulfide polyols, and polycarbonate polyols. If desired, the polyol component may be a mixture of high molecular weight polyols and low molecular weight diols. In one preferred embodiment, the polyol component is a mixture of high molecular weight polycarbonate diol and low molecular weight diol.

Examples of polyether polyols are the following structural formulas;

[Chemical 1] [Where R is hydrogen or a mixed substituent]
A lower alkyl group having 1 to 5 carbon atoms including, n is generally 2 to 6 and m may be 10 to 100 or more. ] A polyalkylene ether polyol containing a polyalkylene ether polyol having
Poly (oxytetramethylene) glycol, poly (oxyethylene) glycol, poly (oxy-1,2-propylene) glycol and ethylene glycol, and 1,2-
It includes the reaction product of a mixture of propylene oxide and ethylene oxide.

It is formed by oxyalkylation of various polyols such as ethylene glycol, 1,6-hexanediol, glycols such as bisphenol A, or higher polyols such as trimethylolpropane and pentaerythritol. Polyether polyols are also useful. The higher functionality polyols that can be used can be made by oxyalkylation of compounds such as sorbitol or saccharose. One commonly available oxyalkylation method is by reacting a polyol with an alkylene oxide, such as ethylene oxide or propylene oxide, in the presence of an acidic or alkaline catalyst.

Polyester polyols can also be used as the polyol component in the present invention. Polyester polyols can be prepared by polyesterification of organic polycarboxylic acids or their acid anhydrides with organic polyols and / or epoxides. Usually the polycarboxylic acids and polyols are aliphatic or aromatic dibasic acids and diols.

The diols usually used when preparing polyesters are alkylene glycols such as ethylene glycol and neopentyl glycol, as well as hydrogenated bisphenol A, cyclohexanediol, cyclohexanedimethanol and caprolactone diols such as ε-caprolactone and ethylene glycol. Included are reaction products, hydroxy-alkylated bisphenols, polyether glycols, such as glycols such as poly (oxytetramethylene) glycol. Higher functionality polyols can also be used. For example, high molecular weight polyols such as trimethylolpropane, trimethylolethane, pentaerythritol, etc., which are also produced by oxyalkylating low molecular weight polyols.

The acid component of the polyester consists predominantly of low molecular weight carboxylic acids or acid anhydrides having 2 to 18 carbon atoms per molecule. Useful acids include phthalic acid,
Isophthalic acid, terephthalic acid, tetrahydrophthalic acid,
Hexaflophthalic acid, adipic acid, azelaic acid, sebacic acid, maleic acid, glutaric acid, chlorendic acid, tetrachlorophthalic acid, decanoic acid, dodecanoic acid, and various other dicarboxylic acids. The polyester may contain minor amounts of monobasic acids such as benzoic acid, stearic acid, acetic acid, hydroxystearic acid and oleic acid. In addition, higher polycarboxylic acid
d), for example, trimellitic acid, tricarballylic acid, etc. may be used. It is understood that in the above mentioned acids, anhydrides of the acids forming the anhydrides can also be used in place of those acids. Lower alkyl esters of acids such as dimethyl glutarate and dimethyl terephthalate can also be used.

Furthermore, in addition to polyester polyols formed from polybasic acids and polyols, polylactone type polyesters can also be used. Such products are formed by reacting a lactone such as ε-caprolactone with a polyol. The products of lactones and acid-containing polyols can also be used.

In addition to polyether and polyester polyols, hydroxy-containing acrylic polymers or acrylic polyols can be used as the polyol component.

Among the acrylic polymers, about 0.2 to 10% by weight of hydroxy-containing vinyl monomers such as hydroxyalkyl acrylates and methacrylates in which the alkyl group has 2 to 6 carbon atoms and ethylenically unsaturated such as alkyl acrylates and methacrylates. There are 90 to 99.8% by weight of copolymerizable material. The weight percent is based on the total weight of the monomer charge.

Examples of suitable hydroxyalkyl acrylates and methacrylates are acrylic and methacrylic acid esters of ethylene glycol and propylene glycol. Also useful are hydroxy-containing esters and / or amides of unsaturated acids such as maleic acid, fumaric acid, itaconic acid.

Examples of suitable alkyl acrylates and methacrylates include lauryl methacrylate, 2-
Ethylhexyl methacrylate and n-butyl acrylate.

In addition to acrylates and methacrylates, other copolymerizable monomers copolymerizable with hydroxyalkyl acrylates and methacrylates include monoolefinic and diolenphinic hydrocarbons, halogenated monoolefinic and diolenphinic hydrocarbons, organic and Ethylenically unsaturated substances such as unsaturated esters of inorganic acids, amides and esters of unsaturated acids, nitriles and unsaturated acids. Examples of such monomers include styrene,
1,3-butadiene, acrylamide, acrylonitrile, α-methylstyrene, α-methylchlorostyrene,
Mention may be made of vinyl butyrate, vinyl acetate, allyl chloride, divinylbenzene, diallyl itaconate, triallyl itaconate, and mixtures thereof. Usually, these other ethylenically unsaturated substances are used in addition to the acrylates and methacrylates mentioned above.

Polysulfide polyols are also useful in the present invention. One such group of materials is the trade name PERMAPOL P-3 polyol commercially available from PRC, Inc. This material is a liquid polyether / thioether diol or polyol. Other types of polysulfide polyols can also be used in the present invention.

The organic polyisocyanate used to prepare the isocyanate-terminated urethane-containing material is usually an aliphatic or aromatic diisocyanate or a mixture of the two. High polyisocyanate (hig
her polyisocyanate) can also be used. Examples of suitable aromatic diisocyanates include 4.4'-diphenylmethane diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate and toluene diisocyanate. Examples of suitable aliphatic diisocyanates include linear aliphatic diisocyanates such as 1,4-tetramethylene diisocyanate and 1,6-hexamethylene diisocyanate. Alicyclic diisocyanates can also be used. Examples include 1,4-cyclohexyl diisocyanate, isophorone diisocyanate, and 4,4′-methylene-bis- (cyclohexyl isocyanate). Examples of suitable high polyisocyanates include 1,2,4
-Benzene triisocyanate, polymethylene polyphenyl isocyanate, and isocyanurates and biurets of the diisocyanates mentioned above.

A preferred aliphatic polycarbonate is Stevens US Pat. No. 3,248,414,
3, 248, 415, 3, 248, 416. These essentially linear aliphatic polycarbonates consist of a number of hydroxyl-terminated carbonates and ether linkages. These patents, all of which are hereby incorporated by reference, include (1) carbon dioxide and 1,2-
Disclosed is the preparation of a polycarbonate from an epoxide; (2) a cyclic carbonate such as ethylene carbonate, or (3) a cyclic carbonate and a 1,2-epoxide. A small amount of polyol is used as an initiator. The reaction is usually carried out under pressure in the presence of metal carbonate, metal hydroxide, tri-sodium phosphate and tertiary amine.

A representative polycarbonate provided using ethylene oxide as the 1,2-epoxide has the following structural formula:

[Chemical 2] [Lower letters m, n, o, etc. in the formula are all positive integers of 1 or more]. Repeating polyethylene oxide unit (
CH ₂ -CH ₂ -O) may vary depending on the length. Therefore, the lower letters m, n, o, etc. are different integers of 1 or more. Usually, this repeating unit is such that the lower letter is no greater than eight. Carbonate units in polycarbonate;

[0024]

[Chemical 3] The numbers range from 2 to 20, but usually the molecule has 3 to 10 units. With different 1,2-epoxides, the repeating units separated by carbonate groups correspond to epoxide ethers and polyethers.

Epoxides that react with carbon dioxide include ethylene oxide, propylene oxide, and 5 carbon atoms.
Up to and including olefinic saturated and unsaturated aliphatic 1,2
Mention may be made of epoxides. Such compounds are often called oxiranes. As another branched epoxide, 4-vinylcyclohexene monooxide or the like can be used. Ethylene oxide is the preferred oxide, although mixtures may be used.

Examples of initiators useful in the preparation of the aforementioned Stevens patented polycarbonate include the structural formula HO
-R-OH, wherein R is an alkylene group of at least 2 carbons and 25 or more carbons], such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol and dipropylene glycol may be used, It can also be used with water. The polyol preferably has from 2 to about 10 carbon atoms, preferably not more than about 4 hydroxyl groups. Compounds with more hydroxyl groups, such as sugars, tend to result in discoloration, and generally the best results are obtained with diols without any ether linkages, such as ethylene glycol and propylene glycol, preferably Is known to be when using the former. Examples of suitable triols include glycerol, trimethylolethane,
And trimethylolpropane. A suitable tetrol is pentaerythritol. Also 1,
Also useful are cycloaliphatic diols such as 3-dihydroxycyclopentane and aromatic dihydroxy compounds such as catechol, bisphenol, and xylene glycol. However, in addition to the polyols, it is possible to use other organic compounds having at least 2 active hydrogens, usually 2 to 4 active hydrogens. Active hydrogen is a hydroxy group,
Means hydrogen bonded directly to a nitrogen atom, a sulfur atom or an oxygen atom as found in non-tertiary amino groups, mercapto groups, carboxyl groups. Such substances include polyamines, mercaptans and alkylol-amines.
amine) etc., and US Pat. No. 3,248,
No. 415, column 6, as exemplified.

Conventional reaction ratios and conditions, eg about 750
Carbon dioxide 1 if a polycarbonate having a molecular weight of from about 5000 to about 5000 and low carbonate bonds is desired.
It is possible to use such as polyols in an amount sufficient to provide 1 to 6 moles of alkylene oxide per mole and 0.01 to 0.2 moles per mole of ethylene oxide. If more carbonate bonds are desired, react an alkylene carbonate such as ethylene carbonate with a polyol such as ethylene glycol at a carbonate to glycol ratio of 1.2: 1 to 2.5: 1 until the ethylene glycol is exhausted. .

The reaction temperature varies between about 160 and about 300 ° C. The polycarbonates that can be used in the present invention can be manufactured by several known methods. For example, the aliphatic diol and the bischloroformate of the aliphatic diol can be reacted in the presence of an inert solvent and an acid acceptor, such as a tertiary amine. According to this method, polycarbonate can be prepared without an ether bond.
Another method is Sears (US Pat. No. 3,186,
961) and Bissinger et al. (US Pat. No. 3,215,668).

Furthermore, polycarbonates can be prepared by transesterification from glycols such as ethylene, propylene and diethylene glycol and dialkyl carbonates such as diethyl carbonate and dimethyl carbonate. Aromatic carbonates such as di-phenyl carbonate can also be used.

In a preferred embodiment, a polycarbonate polyol available under the registered trademark DURACARB from PPG Industries, Inc. can be used. Generally, suitable polycarbonate diols have a number average molecular weight of about 150 to about 10,000, preferably about 500 to about 5000, more preferably 850 to 2000. The number average molecular weight is determined by gel permeation chromatography (GPC) using a polystyrene standard.

The isocyanate groups of the isocyanate-terminated urethane-containing material can be blocked if desired. In a preferred embodiment, the isocyanate groups may be blocked after the isocyanate-terminated urethane-containing material has been prepared, or the polyisocyanates may be partially blocked prior to reaction with the polyol component. Alternatively, the polyisocyanate may be reacted with a portion of the polyol component, then partially blocked, followed by the remaining polyol and blocking agent. Blocking of isocyanate groups can be used as a means of forming a stable one-package system. Isocyanate-terminated urethane-containing materials with free isocyanate groups can be used to form two-package room temperature cure systems.

Various types of blocking agents can be used. Examples of suitable blocking agents are lower aliphatic alcohols such as methanol; oximes such as methyl ethyl ketone oxime; and lactams such as .epsilon.-caprolactam, which release the block at high temperatures.
As a preferred specific example of the present invention, the isocyanate group of the urethane-containing substance having an isocyanate terminal group is ε-
It is blocked with caprolactam.

The isocyanate-terminated urethane-containing material is used in an amount of about 50 percent to about 95 percent, preferably about 80 percent to about 90 percent, based on the total resin solids of the coating. Can be present inside. Small changes in these amounts are not particularly limited to the above limits.

The second important component of the coating used in the present invention is an essentially oxirane-free phosphated polyepoxide. Phosphated polyepoxide is a substance having 1,2 epoxide groups in the molecule. Hydroxyl groups may or often are present. Polyepoxides contain one or more 1,2-epoxy groups per molecule. Generally the epoxide equivalent weight is about 280
It can range from up to about 4000. Such polyepoxides are saturated or unsaturated, cyclic or acyclic, aliphatic, cycloaliphatic, aromatic or heterocyclic.
They can contain substituents such as halogen, hydroxyl and ether groups.

One useful class of polyepoxides consists of epoxy polyethers obtained by reacting epihalohydrins (such as epichlorohydrin or epibromohydrin) with polyphenols in the presence of alkali. Suitable polyphenols include resorcinol,
Catechol, hydroquinone, bis (4-hydroxyphenyl) -2,3-propane, ie bisphenol A; bis
(4-hydroxyphenyl) -1,1-isobutane, 4,4
-Dihydroxybenzophenone; bis (4-hydroxyphenyl) -1,1-ethane; bis (2-hydroxynaphthenyl) -methane; and 1,5-hydroxynaphthalene. One very common polyepoxide is the polyglycidyl ether of a polyphenol such as bisphenol A. Another class of epoxy resins are polyglycidyl ethers of polyhydric alcohols. Such compounds include ethylene glycol, diethylene glycol,
Triethylene glycol, 1,2-propylene glycol, 1,4-butylene glycol, 1,5-pentanediol, 1,2,6-hexanetriol, glycerol,
It can be obtained from trimethylolpropane and polyhydric alcohols such as bis (4-hydroxycyclohexyl) -2,2-propane.

Another class of epoxide resins are the polyglycidyl esters of polycarboxylic acids. Such compounds include epichlorohydrin or similar epoxy compounds and oxalic acid, succinic acid, glutaric acid, terephthalic acid,
It is produced by reaction with an aliphatic or aromatic polycarboxylic acid such as 2,6-naphthalenedicarboxylic acid and dimerized linoleic acid.

Another class of further polyepoxides results from the epoxidation of olefinically unsaturated cycloaliphatic compounds. Such polyepoxides are non-phenolic and are obtained by epoxidation of cycloaliphatic olefins, such as oxygen and a metal catalyst of choice, perbenzoic acid, acid-aldehyde monoperacetate, or acetic acid. Among such polyepoxides, epoxy cycloaliphatic ethers and esters are well known in the art.

Useful epoxides also include those containing an oxyalkylene group in the epoxy molecule. Another class of polyepoxides consists of epoxy novolac resins. Such resin is epihalohydrin,
It can be obtained by reacting an aldehyde with a monohydric or polyhydric phenol condensate. A typical example is the reaction product of epichlorohydrin and phenol formaldehyde condensate.

Another group of epoxide-containing materials is acrylic copolymers containing copolymerized glycidyl acrylate or methacrylate units. Such an acrylic copolymer can be prepared by reacting an alkyl ester of an α, β, unsaturated mono- or dicarboxylic acid with glycidyl acrylate or methacrylate. Other glycidyl-containing copolymerizable monomers such as diglycidyl itaconate and diglycidyl maleate can also be used. Such monomers can optionally be copolymerized in the presence of vinyl aromatic compounds, such as styrene or vinyltoluene, and other copolymerizable monomers such as acrylonitrile or methacrylonitrile.

It should be understood that mixtures of the aforementioned polyepoxides can be used if desired. The aforementioned polyepoxides are phosphatized such that they are essentially free of oxirane groups. Phosphation is carried out by co-reacting the polyepoxide with a source of orthophosphoric acid and hydrolyzing the resulting product. It is believed that the hydrolysis process is important in obtaining an essentially oxirane-free product.

Examples of the phosphoric acid source substance include 100% orthophosphoric acid, hemihydrate 2H ₃ PO ₄ .H ₂ O and aqueous solutions. Condensates of phosphoric acid such as pyrophosphoric acid and triphosphoric acid can also be used. Representative phosphoric acid aqueous solutions, especially 70 to 90% solutions, are preferred.

The epoxide-acid reaction can be carried out with or without a reaction medium. A reaction medium is preferably used. Examples of suitable media include acetone, methyl ethyl ketone, methylene chloride, diethylene glycol monobutyl ether, glycol ether, isopropanol, and ethanol.

The reaction is usually carried out by dissolving the selected polyepoxide or mixture of polyepoxides in the desired medium, if used, and adding the phosphoric acid source. The mixture heats and exotherms. The mixture is then hydrolyzed with water and the product cooled.

Hydroxyl-functionalized phosphatized polyepoxides are essentially free of oxirane groups and generally have a number average molecular weight of from about 200 to about 100,000. The ratio of hydroxyl equivalents in the phosphatized polyepoxide to isocyanate equivalents in the isocyanate-terminated urethane-containing material is generally about 0.5: 1 to 1.5: 1.

The phosphatized polyepoxide is present in the claimed coating in an amount ranging from about 5 percent to about 49 percent, preferably 9 percent to 15 percent, expressed as a percentage based on the total solids content of the coating. .

In one embodiment of the invention, the phosphatized polyepoxide essentially free of oxirane groups is formed by reacting at least a portion of the hydroxyls of the oxirane group-free phosphated polyepoxide with an organic polyisocyanate. It should be understood that the isocyanate-terminated prepolymer may be present. If desired, the isocyanate groups can be blocked as described above. When all the hydroxyls are reacted during the formation of the prepolymer, an active hydrogen-containing substance such as a polyol can be further added as a crosslinking agent.

A very important aspect of the above-mentioned paint is its flexibility, as evidenced by the elongation of the cured coating. The claimed coatings generally have an elongation when cured of at least 50%, preferably at least 100%, more preferably from about 200% to about 300%. Elongation rate is ASTM-
According to No. 72, Instron Tester
To decide. The test is run at a speed of 20 inches per minute using a sample measuring width of 0.25 inches.
The sample is examined with a "free-standing film", i.e. removed from the support. (Simply, the coating is applied on a support that has been pretreated with a release agent that facilitates peeling of the cured coating from the support). The flexibility of the coatings used in the present invention is particularly advantageous when the coatings are utilized as metal undercoats in forming multilayer coating supports. The flexibility of the subbing agent greatly contributes to the flexibility of the multi-layer coating system. This flexibility is particularly useful in the field of coil application, as the coil with a flat support can be coated first and then incorporated into the desired article without compromising the appearance properties.

Another important aspect of the coating composition described above is its excellent adhesion, especially when incorporating coated parts and when exposed to harsh environments. It exhibits outstanding durability as well as outstanding flexibility.

It should be understood that, in addition to the above-mentioned components, the above paint as a primer may also contain pigments and additives known to those skilled in the art. In addition, paints are generally prepared in a suitable solvent to facilitate formulation and application.

Several different pigments can be used in the paint. Useful inorganic pigments include titanium dioxide, silica, iron oxide, talc, mica, clay, zinc oxide, strontium chromate, carbon black, lead chromate, molybdenum orange, calcium carbonate, barium sulfate and the like. Organic pigments can also be used in the present invention.

Suitable solvents include aromatic petroleum fractions, cyclohexane, methyl ethyl ketone, methyl isobutyl ketone, alcohols such as ethyl alcohol, propyl alcohol and diacetone alcohol, dimethyl phthalate, and mono- and di-alkyl ethylene, diethylene glycol. Ethers such as ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether and diethylene glycol diethyl ether can be mentioned.

Examples of conventional additives include surfactants, antioxidants, ultraviolet absorbers, stabilizers, flow control agents and coalescing aids.

The thermosetting coatings are typically prepared by combining the ingredients together with gentle agitation. When the paint is formulated as a single package system that blocks isocyanate-terminated urethane-containing materials, typically other tin catalysts such as dibutyltin dilaurate or dibutyltin diacetate or dibutyltin oxide, etc. Of the catalyst is required. Single package paint is about 450 ° F (232 ° C) to about 500 ° F
Peak metal temperature in the range (257 ° C)
It can be cured by heating (ture). It is believed that the isocyanate blocking agent liberates upon heating, facilitating urethane formation between the isocyanate and hydroxyl groups.

In the method for producing a support having a multilayer coating film of the present invention, as a first step, (a) a support is coated with a flexible undercoat paint. The primer has an elongation of at least 50% when cured. As the undercoat paint used in the first step of the present method, those described in detail above can be used. As mentioned above, an important aspect of basecoats that ultimately provides the flexibility of multilayer coatings is the flexibility as evidenced by elongation.

The claimed method is suitable for coating a wide range of metal supports such as steel and aluminum. A variety of steel supports are available, any of which are suitable for the present invention, for example cold rolled steel, hot dip plated steel, aluminum vapor deposited steel, as well as steel coated metal sheets of zinc / aluminum alloys. When the undercoat paint is applied to the support, the second step (b)
In, the colored paint is applied to the coated support of (a).
The pigmented coating can be applied onto the wet base coat and the coated support can be subsequently coated without first drying. The primer may be baked and partially cured prior to applying the pigmented coating. In a preferred embodiment, about 2% before the application of the colored paint in step (b)
About 20 seconds to about 18 at a temperature of 00 ° C to about 260 ° C
Bake the coated support of step (a) for 0 seconds.

Step (a): a step applied on the undercoat paint
The colored paint of (b) is polyester resin, acrylic resin,
It can be selected from a wide range of colored paints such as fluorocarbon resins and paints based on vinyl resins such as plastisol. In one preferred embodiment, the pigmented coating comprises fluorocarbon. Preferably, the pigmented coating further comprises, unlike the fluorocarbon polymer, an auxiliary polymer suitable for modifying the properties of the fluorocarbon polymer. The auxiliary polymer is preferably an acrylic polymer.

Several different film-forming fluorocarbon polymers are useful in the present invention. Examples of such a polymer include polyvinyl fluoride, polyvinylidene fluoride, vinyl fluoride copolymer, vinylidene fluoride copolymer and the like. The preferred film forming fluorocarbon polymer is polyvinylidene fluoride. The copolymer comprises at least 75% by weight of vinyl or vinylidene fluoride units, preferably 90% by weight or more. Examples of the monomer copolymerizable with vinyl fluoride or vinylidene fluoride include ethylene, propylene, isobutylene, styrene, vinyl chloride, vinylidene chloride, difluorochloroethylene, tetrafluoroethylene, trifluoropropylene, hexafluoropropylene, vinyl formate, Vinyl acetate, vinyl propionate, vinyl butyrate, acrylic acid and its salts, methyl methacrylate, allyl methacrylate, acrylonitrile, methacrylonitrile,
Examples thereof include N-butoxymethyl acrylamide, allyl acetate, and isopropenyl acetate. Generally, the amount of fluorocarbon polymer is
It is in the range of about 45 wt% to about 85 wt%, preferably about 65 wt% to about 75 wt% of the claimed paint, based on a percentage based on the total weight of the resin component of the paint.

The auxiliary polymer can be selected from a wide range of polymeric materials suitable as modifiers for fluorocarbon resins. Examples of suitable modifiers include polyester resins such as acrylic resins and polyols, epoxy resins, aminoplast resins such as melamine-formaldehyde condensates.

The particular auxiliary resin selected will depend on the properties desired when modifying the fluorocarbon resin. For example, if a softer, more flexible coating is desired, a polyester resin can be selected, and if hardness is desired, an aminoplast resin, acrylic acid or epoxy resin can be selected. . Mixtures of these auxiliaries can also be used.

Preferably, the auxiliary resin is an acrylic polymer. The acrylic polymer may be a thermoplastic resin or a thermosetting resin. Suitable thermoplastic acrylic polymers are polymers and copolymers of acrylic acid or methacrylic acid esters, such as acrylic acid or methacrylic acid with suitable alcohols such as methyl alcohol, ethyl alcohol, propyl alcohol, butyl alcohol and 2-ethylhexyl alcohol. Mention may be made of ester polymers and copolymers formed by the reaction. One preferred thermoplastic acrylic resin is a copolymer of methyl methacrylate and ethyl acrylate. Thermosetting acrylic polymers are preferred in one embodiment. Suitable thermosetting acrylic polymers include active hydrogen containing acrylic monomers such as hydroxyalkyl esters of ethylenically unsaturated carboxylic acids and polymers and copolymers of at least one other copolymerizable ethylenically unsaturated monomer. Can be mentioned.
For example, suitable thermosetting resins are prepared from 2-hydroxyethyl acrylate, acrylic acid, N-butoxymethyl acrylamide and other copolymerizable ethylenically unsaturated monomers such as styrene, vinyltoluene, methylstyrene, or ethylstyrene. It is what is done. The amount of acrylic polymer is a percentage based on the total weight of the resin component of the coating and typically ranges from about 15% to about 55%, preferably from about 25% to about 35%.

The polyester and epoxy resins mentioned above in connection with the base coat can also be used as auxiliary resins. These have been described in detail above and will not be described further here. Aminoplast resins can also be used as auxiliaries, these are mentioned below. Aminoplast is an adduct of formaldehyde with an amino- or amino group carrier. Condensates of alcohols and formaldehyde with melamine, urea or benzoguanamine are the most common and are preferred in the present invention. The condensate may have a low molecular weight or a high molecular weight. Condensates of other amines and amides such as triazines, diazines, triazoles,
Aldehyde condensates such as guanazine, guanamine, and alkyl- and aryl-substituted derivatives of these compounds, alkyl- and aryl-substituted ureas, alkyl- and aryl-substituted melamines can also be used. Examples of such compounds include N, N-dimethylurea, benzourea, dicyandimide, formaguanamine, acetoguanamine, glycoluril, ammeline 2-chloro-4,6.
-Diamino-1,3,5-triazine, 6-methyl-2,
4-diamino-1,3,5-tolidine, 3,5-diaminotriazole, triaminopyrimidine, 2-mercapto-4,6-diamino-pyrimidine, 3,4,6-tris (ethylamino) -1,3 1,5-triazine and the like can be mentioned.

The aldehyde used is most often formaldehyde, but other similar condensates can be prepared from other aldehydes such as acetaldehyde, crotonaldehyde, acrolein, benzaldehyde, furfural, glyoxal and the like.

Aminoplast resins contain methylol or similar alkylol groups, and in most cases at least a portion of these alkylol groups have been etherified by reaction with an alcohol to provide an organic solvent soluble resin. is doing. Any monohydric alcohol can be used for this purpose, and examples of such alcohols include methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, etc., as well as benzyl alcohol, aromatic alcohol, cyclohexanol, etc. Cyclic alcohol, CELLOSOLV
SOLVES) and carbitol (CARBITOL)
Monoethers of glycols such as S) and alcohols substituted with halogen or other substituents, eg 3
-Chloropropanol and butoxyethanol may be mentioned.

In a more preferred embodiment of the present invention,
After applying the color paint to the undercoat support, the third method (c)
In the step, a transparent paint is applied to the coated support of (b). As described in the step (b), the transparent paint may be applied on the colored paint in a wet state, or may be baked and partially cured before the application of the colored paint. In a preferred embodiment, about 2% prior to applying the clear coat of step (c).
About 20 seconds to about 18 at a temperature of 00 ° C to about 260 ° C
Bake the coated support of step (b) for 0 seconds.

The transparent paint of step (c) applied on the colored paint of step (b) can be selected from various transparent paints.
In a preferred embodiment, the clearcoat comprises a fluorocarbon polymer. Preferably, the clearcoat further comprises an auxiliary polymer adapted to modify its properties, rather than a fluorocarbon polymer. The auxiliary polymer is preferably acrylic acid. In a preferred embodiment, the clearcoat comprises about 45% to about 85% fluorocarbon polymer and 15% to 55% acrylic polymer based on resin solids. More preferably,
The clearcoat comprises about 65% to about 75% fluorocarbon polymer and about 25% to about 35% acrylic polymer based on resin solids. The fluorocarbon polymer and acrylic polymer are detailed above in connection with the pigmented fluorocarbon polymer of the coating of step (b). The auxiliary polymers detailed above can also be used here.

The clear paint may incorporate the same types of solvents and additives as described in connection with the colored paint. When the clear coat is applied, the base coat coated with the color paint and the clear coat is about 20 seconds to about 180 seconds, about 20 seconds.
Bake at a temperature of 0 ° C to about 260 ° C. This last baking step has the effect of removing the solvent as well as fusing the coating layers together in some bonding process.

The multilayer coating support is at least 50%, preferably at least 100%, more preferably about 200%.
It is very flexible as evidenced by the elongation of the cured system in the range of to 300%. Elongation is determined as described for the basecoat. Furthermore, the coated substrate has excellent durability, weather resistance and harsh environmental resistance.

The multi-layer coating system of the present invention can be prepared in various dry coating thicknesses depending on the number of layers and the thickness of each layer.
For a three-layer system, the coating thickness for that system is typically 2.0.
It is in the range of mils to 4.5 mils. For a two layer system, the dry film thickness of the system is usually from about 1.0 mil to about 3.
It is in the 0 mil range. The basecoat dry film thickness is usually in the range of about 0.2 mils to about 1.5 mils; the pigmented paint dry film thickness is in the range of about 0.5 mils to about 1.5 mils; And the dry film thickness of the clear coating is in the range of about 0.2 mils to about 1.0 mils. The present invention can be formed to a thickness outside the above range, and is not particularly limited to the above range.

[0069]

The claimed multi-layer coated substrate has at least an elongation of 50% and is easy to fabricate; it also has excellent adhesion, abrasion resistance, surface rub resistance, weather resistance. , Shows industrial pollution resistance. The transparent coating greatly contributes to this result. In addition, it acts as a barrier, minimizing the migration of corrosive contaminants to the underlying layer and is also very important for surface rub resistance.

[0070]

The following examples are merely illustrative of the claimed invention and are not intended to limit the invention.

[0071]Example I  This example is a block for use in accordance with the present invention.
Preparation of urethane-containing substances with isocyanate-terminated groups
Will be explained. (1) Polycarbonate having the hydroxyl group as an end group
Toluene has a nominal molecular weight of 850, 121 to 14
Having a hydroxyl number in the range of 7, PPG Industries
Available commercially from stock companies.

Charge I was charged into a reaction vessel equipped with a thermometer, a stirrer, and a nitrogen inlet tube, and heated to a temperature of about 80 ° C. When the reaction exotherm had ceased and the temperature had subsequently dropped, the reaction mixture was heated to about 95 ° C. and held at that temperature until the isocyanate equivalent weight measured was constant. Then, the mixture is cooled to about 70 ° C. and charged (II) and (III)
Was added. The reaction mixture was heated to about 95 ° C. and held at that temperature until no isocyanate was visible by infrared absorption. The resulting product had a number average molecular weight of 2345 as determined by gel permeation chromatography (GPC) using polystyrene standards. 77.8% total solids and Z4 determined at 110 ° C. for 1 hour
It had a Gardner Viscosity of.

[0073]Example II  Phosphated epoxides that are essentially free of oxirane groups
It was prepared according to the invention as follows. (2) Mixing 50% methyl amyl ketone and 50% xylene
EPON 836 (Shell Chemical Co., Ltd.)
commercially available from emical Co.)) 75% solution. Last
A typical solution is 60% total solids and 28% solids.
It had an epoxy equivalent weight of 0 to 400.

Charge (I) into an appropriately equipped reaction vessel,
Stir for 15 minutes. Then Charge (II) was added and the mixture was heated to 80 ° C. When the reaction mixture begins to exotherm,
Approximately 104 ° C when heating is stopped and the mixture remains exothermic
Became. The reaction mixture was cooled and kept at a temperature of 80 ° C. for about 30 minutes. Charge (III) was then added, the reaction mixture was held for 2 hours at about 75 ° C. and cooled.
The product obtained is 65.1, determined at 150 ° C. for 1 hour.
% Total solids, Z3 to Z4 Gardner viscosity, infinite epoxy equivalents.

[0075]Example III  This example illustrates the preparation and physical properties of the paint used in this invention.
The evaluation of the characteristics will be described. (3) Phosphated Epo substantially free of oxirane
Kish was prepared in Example II above. (4) Terminate this blocked isocyanate
The urethane-containing material was prepared in Example I above. (5) The pigment paste was prepared as follows. The compounding agents are combined in the order shown and ceramic beads are used.
Crushed to No. 7 Hegman. Continued
Then, 20.0 parts by weight of diacetone alcohol was added.
The paste had 60.2% total solids.

(6) L-O-B L 275 (L
O-VEL 275) commercially available from PPG Industries Ltd. A coating material was prepared by sequentially combining the above-mentioned ingredients with gentle stirring. The resulting coating had a total solids content of 60.0%. A test panel for evaluation was prepared as follows. 4 inch x 12 inch hot dip plated steel panel (bonder light 1303
G which has been pre-processed by (BONDERITE 1303)
90HDG) and the coating film detailed above has a dry film thickness of 0.8.
It was applied using a wire wound bar so that it would be a mil. The panels were baked for 40 seconds to a peak metal temperature of 465 ° F (240 ° C). Cured coating is AST
Instron Tester (Instr
on Tester) had an elongation of 230 to 290%. After the secondary processing of the cured coating film, the pencil hardness, solvent resistance and adhesiveness were also evaluated.

Pencil Hardness : This is a measurement of the resistance of the coating to a pencil indenter. Pencil hardness grades begin with 4B, which is a relatively soft coating, and increase to 10H, which is a relatively hard coating, as follows: 4
B, 3B, 2B, B, HB, F, H, 2H, 3H ...
・ Up to 10H.

Solvent Resistance : This is a measure of the coating's ability to withstand 100 double rubs with a sponge pad soaked in methyl ethyl ketone. The number of rubs is the number of double rubs on the coating. "No effect" means that the coating showed no visible evidence of deleterious results as a result of testing the solvent. The numerical rating means that the coating was highly damaged and that the support was visible after a given number of double rubs.

T-Flex Adhesion : Coatings were evaluated for cracking and loss of adhesion after bending coated panels to varying degrees. A 3T bend means that the bend diameter is three times as thick as a steel panel. 2T bending is
It means that the bending diameter is twice as thick as the steel panel, and so on. OT bending means bending at 180 degrees and compressing flat.

The coating was cracked and visually observed for removal of the coating after a piece of adhesive tape was pressed onto the surface of the coating and quickly stripped from the coating. Grades were assigned on a scale of 1-9. A score of 9 indicates no cracks and no coating removal with tape, while a score of 0 indicates severe cracking and complete removal of coating with tape. Scores in between indicate varying degrees of cracking and coating removal.

The coating film is "Nickel Scratch".
The amount of adhesion loss determined by the "ch)" test was also evaluated. In this test, the nickel edge was firmly pulled down along the coating. Areas so tested were observed for coating removal. The results were evaluated on a scale of 0 to 9, with a score of 9 indicating no coating removal at all, and a number of 0 indicating complete removal of coating, as described above.

The results are detailed below. Pencil hardness H Solvent resistance (greater than 100 double rubs) No effect Nickel scratch 6 3T (crack / tape peeling) 9/9 2T (crack / tape peeling) 8/9Example IV  This example provides a three coating multi-layer support according to the invention.
The method and evaluation of the physical properties of the multilayer coating are described.A. Preparation of undercoat paint  The primer used in this example was detailed in Example III.
It is a thing. B. Preparation of colored paint

(7) This thermosetting acrylic polymer is
62% methyl methacrylate, 27% ethyl acrylate, 9% N-butoxymethyl acrylamide, and 2
% Methacrylic acid copolymer is an isophorone solution having a resin solid content of 50%.

(8) This ester is a DB (DB
E) as E. Eye. Dupont Donne Morse (EIDup
commercially available from ont de Nemours).

(9) The melamine formaldehyde cross-linking agent is Monsanto Chemical Corporation (Monsanto Ch
commercially available from Emical Corporation).

(10) This crushed paste is prepared from the following prescribed proportions of the compounding ingredients. (a) The 2-ethylhexyl acrylate homopolymer is commercially available as MODAFLOW from Monsanto Che
Commercially available from mical Corporation. The crushed paste is prepared by adding ceramic beads to the compounding agent, stirring the mixture at high speed, and processing it into 7.5 Hegman crushed products.

(11) A polyvinylidene fluoride pigmented paint commercially available from Pennwalt is compounded, agitated with ceramic beads at high speed to 5.5.
Prepared as Hegman grind. C. Preparation of transparent paint

(12) The acrylic polymer is described in detail in Note 7. (13) Davison as SYLOID 308 (Dav
ison) commercially available. The clear paint is prepared by combining the ingredients and stirring at high speed with ceramic beads to give 5.5 Hegman grounds. The test panel was prepared as follows.

4 inch x 12 inch hot dip plated steel panel (bonder light 1303 (BONDERI
The coatings detailed in Example III were applied to G90HDG) pretreated with TE 1303) using a wire wound bar to a dry film thickness of 0.8 mil.
The panels were baked for 40 seconds to a peak metal temperature of 465 ° F (240 ° C). The coated panel was then coated with the fluoropolymer-based colored coating detailed above at a film thickness of 0.8 mils and a peak metal temperature of 465 ° F (240 ° C) for 40 seconds. Burned Finally, the panels coated as detailed above were 0.8 mil thick finish coated with a clearcoat based on the fluoropolymer detailed above. And the coated metal panel is 465 °
It was baked at a peak metal temperature of F (240 ° C.) for 40 seconds. The elongation of the cured three-layer multilayer coating is ASTM
It was 70% as determined by an Instron tester according to D638-72. In addition to the tests described in Example III above, the physical properties were evaluated according to the following tests. The results are shown in Table I below.

Test Salt Spray: Prior to carrying out this test, a coated test panel was prepared as follows: score marks were scored along the center length of the panel; the three edges of the panel were trademarked MUs.
Coated with a protective basecoat commercially available from PPG Industries, Inc. as LTIPRIME, exposing only one edge; and bending the panel 120 °. The surface of the panel was a flat surface with no depressions or marks.

The coated test panel was tested according to ASTM B117
At 100 ° F (38 ° C) and 100% relative humidity according to
% Salt solution) sprayed continuously. Average amount of notch marks, bends, and corrosion or loss of paint spreading from edges (indentation creep, bending creep, edge creep), and panel surface blister (bl
The amount of istering) was evaluated. It was rated on a scale of 0 to 10 for the amount of nicks, bends and spread of corrosion from the edges. A score of 0 for creep is 7/8 for 1 inch from corrosion scoring, bending, or edge.
It means that it has spread over an inch. A score of 10 means that there is essentially no corrosion spreading from a particular area. Values within the endpoints of the scales shown indicate varying degrees of corrosion extending from a particular point as described below.

[0092]Average corrosion measurements Evaluation inch Mm  0 0 10 1/64 0.4 9 1/32 0.8 8 1/16 1.6 7 1/8 3.2 6 3/16 4.8 5 1/4 6.4 4 3/8 9.5 3 1/2 12.7 2 5/8 15.9 1 7 / 8 to 1 or more 25 or more 0

The panel is 0 to 10 with respect to the amount of blistering.
The scale was evaluated. A score of 10 for blisters means that there is essentially no blisters within the designated area of the panel. A score of 0 means that more than 75% of the given areas have blisters. The values within the endpoints of the scale shown indicate varying degrees of blistering that emanate from a particular point as described below. The swelling density was evaluated by the following letters: F (little), M (normal), D (dense).

[0094]

Moisture resistance : For this test, the coating test panel was fitted with a condensing humidity chamber (QCT).
The coating was used as the ceiling of the room, facing the inside of the room. The chamber is heated to 140 ° F (60 ° C) and water at about 2 inches of water is placed under the test panel (panel is tilted) 3
Or 5 inches.

The panels were rated on a scale of 0 to 10 for blistering as described above. The panel was also evaluated for the amount of adhesion loss determined by the "nickel scratch" test.

Back Impact Test : The cured coating was ASTM D2
60, 90, and 120 inch-pound backside impact tests were performed according to 794. The impact-tested coatings were visually observed for crack content and removal of the coating after a piece of adhesive tape was pressed onto the surface of the coating and quickly stripped from the coating. The grade was scaled from 1 to 9. A score of 9 indicates no cracks and no coating removal with tape, while a score of 0 indicates severe cracking and complete removal of coating with tape. Scores in between indicate varying degrees of cracking and coating removal. The results are shown in Table I below.

[0098]Example V  This example illustrates various blocked isocyanates according to the present invention.
Explaining the preparation of urethane-containing materials with anate end groups
To do.

(14) TERACOL 650; The hydroxyl-terminated polyether polyol is EIDuPont.
Commercially available from de Nemours. It had a molecular weight of 650 and a nominal hydroxyl number of about 173.

This preparation was carried out as described in Example I above. The resulting product is G using a polystyrene standard.
It had a number average molecular weight of 1824 as determined by PC; 79.6% total solids and Z-1 Gardner viscosity determined at 110 ° C. for 1 hour.

[0101]Example VI  This example is a coating using the urethane-containing material of Example V.
The preparation of the material and the evaluation of physical properties are described.

(15) The pigment paste was prepared as follows. The compounding agents were compounded in the order shown to use ceramic beads, and crushed into No. 7 Hegman crushed products.

(16) Prepared in Example V above. A coating material was prepared by sequentially combining the above-mentioned ingredients with gentle stirring. The resulting coating had a total solids content of 60.0%. A test panel for evaluation was prepared as in Example III above. After the secondary processing of the cured coating film as described in Example III, the pencil hardness, solvent resistance and adhesiveness were also evaluated.
The cured coating had an elongation of 200 to 300 as determined by an Instron tester according to ASTM D638-72. The results are shown below.

Pencil hardness F Solvent resistance (double rub) 48 Nickel scratch 6 3T (crack / tape peeling) 9/9 2T (crack / tape peeling) 8/9

[0105]Example VII  This example is a support for a three-layer multilayer coating system according to the present invention and
And evaluation of physical properties will be described. This example is used for this example.
Except that the primer used is that described in Example VI above.
Is the same as in Example IV. The evaluation results of physical properties are shown in Table I.
It is shown in.

[0106]Table I  3-layer multi-layer system  Example IV Example VI test of of  Undercoat Undercoat  Pencil hardness HB HB Solvent resistance (more than 100 double rubs) No effect No effect Nickel scratch 7 3 T-Bending adhesion (crack / tape peeling) 3T 9/9 9/9 2T 9/9 9/9 Salt spray * Gradual creep Phenomenon 8 6-5 Bending creep phenomenon 10 10 Edge creep phenomenon 7 7 Bulging surface 10 10 Moisture resistance * Bulging 10 2 Adhesion 3 1 Backside impact test (crack / tape peeling) 60 inch-pound 9/9 9/9 90 inch -Pound 8/9 9/9 120 inches-Pound 8/9 8/9 * 1000 hours for Example IV system 500 hours for Example VII system

[0107]Example VIII  This example is a sub-layer of a two-layer multilayer coating system support according to the present invention.
The preparation method will be described. Three different two-layer systems were prepared and
The physical characteristics were evaluated.System ACarried out the paint of Example III
Apply to hot dip plated steel as described in Example III
Prepared. Panels applied while still wet
P under the trademark name POLYCRON Super D topcoat
Poly available commercially from PG Industries Ltd.
An ester finish was applied. Panel at 465 ° F (240
(° C.) Peak metal temperature for 40 seconds.System BIs po
Basically fluorocarbon instead of reester finish
Prepared in the same manner as System A, except using a finish coat
It was This topcoat has the trade name DURANAR topcoat
Commercially available from PPG Industries, Inc.
is there. System C is the poly of Example III used as a primer.
Instead of the carbonate-based paint, the undercoat is actually
Prepared in the same manner as System B except that it was the paint of Example VI.
The finish coat again uses the brand name DURANAR topcoat
It was Tests described in Examples III and IV for each two-layer multilayer system
The physical properties were evaluated according to. The results are shown in Table II below.
It was

[0108]

[0109]Example IX  This example is essentially an alternative to the coating used in the present invention.
The criticality of phosphatized polyepoxides without xylan groups
explain.Part A  Essentially non-phosphatization of the oxirane group (hydrolysis
Essentially free of oxiranes over epoxides)
Comparative Phosphated Epoxides
Poxide was adjusted as follows.

Charge I into a suitably equipped reaction vessel and heat in vacuum to a temperature of about 65-75 ° C. for about 6 hours,
All solvent was distilled off. The mixture was stirred and cooled. The mixture was subsequently heated to about 50 ° C. under a nitrogen atmosphere and Charge II was added. The mixture was refluxed for about 90 minutes and Charge III was added. Reaction mixture for 8 hours at about 60 ° C
Held in. Then, Charges IV and V were added under a nitrogen atmosphere, and reflux was continued for about 7 hours. The solvent was distilled off. The mixture was cooled to 80 ° C.

500 g of acetone was added to the above mixture. Some evaporated and escaped, so an additional 19.9 g was added. The mixture was maintained at 80 ° C. and 200 g of acetone was added to facilitate filtration. The filtrate was heated to reflux under a nitrogen atmosphere to remove the solvent. The product obtained was analyzed by GPC using 1024 polystyrene standards.
It had a number average molecular weight as determined in 1 .;
58.8% solids determined by time, and Z-Z1
Had a viscosity of. The paint was as follows. Paint 1 : A paint detailed in Example III utilizing a phosphated epoxide essentially free of oxirane groups Paint 2 : This paint is the same as Example III except that the hydrolyzed epoxide detailed above is incorporated. Each paint was applied and solvent resistance and pencil hardness were evaluated as described in detail in Example III. The panel was T-bent without any tape stripping of the coating and the amount of T-bending was evaluated. The results are shown below.

[0112] Each paint is POLYCRON, trade name of Example VIII above
It is also used to prepare a two-layer multilayer coating system using Super D polyester coating. This system evaluated salt spray and humidity.

[0113] The non-phosphated epoxide reference system was inferior in solvent resistance, adhesion measured by T-bending, moisture resistance, and salt spray.

[0114]Part B  Of phosphated epoxides essentially free of oxirane groups
Oxirane-containing epoxide (non-phosphated, unhydrolyzed)
Against. The paint was as follows:Paint 3 : Phosphated epoxide essentially free of oxirane groups
Coatings detailed in Example III utilizing sidPaint 4 : This paint is non-phosphated, unhydrolyzed EPON
Same as Example III except that 836 was added.

Each paint was applied and evaluated for solvent resistance and pencil hardness as detailed in Example III. The results are shown below. The coating material containing the oxirane-containing epoxide did not cure sufficiently and the coating film was easily scratched. Therefore, the support became visible only after seven round trips with the solvent.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Internal reference number FI Technical display location B32B 27/40 7016-4F (72) Inventor Robert Allan Montague United States Pennsylvania 15101, Allison Park, Laurel Oak Drive 4443 (72) Inventor Marvin Theodor Tettenbaum Pennsylvania 15090 United States Pennsylvania 15090, Wexford, Salisbury Court 2919 (72) Inventor Error James Van Buskerk Pennsylvania 15237 United States Pittsburgh 15237 , Darrell Drive No. 9222

Claims (9)

[Claims] 1. A coating of (a) a flexible undercoating on a support; said coating comprising (i) an isocyanate-terminated urethane-containing material; and (ii) phosphorus essentially free of oxirane groups. (B) applying at least one pigmented coating to the coated support of (a); (c) at least partially curing the coated support of step (b); A method of making a multilayer coating film support having an elongation of at least 50% when the multilayer coating film is cured. 2. The method of claim 1 further comprising the step of applying a clear coating to the coated support of step (b) prior to at least partially curing the coated support. 3. The method of claim 1 wherein the colored coating of step (b) comprises a fluorocarbon polymer. 4. The method of claim 3 wherein the colored polymer further comprises a co-polymer suitable for modifying the properties of the fluorocarbon polymer, rather than the fluorocarbon polymer. 5. The method of claim 4, wherein the auxiliary polymer is an acrylic polymer. 6. The method of claim 1, wherein the clear coat comprises a fluorocarbon polymer. 7. The method of claim 6 wherein the clearcoat material further comprises an auxiliary polymer suitable for modifying the properties of the fluorocarbon polymer rather than the fluorocarbon polymer. 8. The method of claim 7, wherein the auxiliary polymer is an acrylic polymer. 9. The method of claim 1, wherein the dry film thickness of the primer coating is in the range of 0.2 mils to 2.0 mils.